[wasm] Refactor encoder.h to use a proper buffer and remove OldFunctions section.

src/wasm/wasm-js.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/api-natives.h"
 #include "src/api.h"
 #include "src/assert-scope.h"
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/execution.h"
@@ skipping 103 matching lines @@
                                                 buffer.start, buffer.end);
   }
 
   if (result.failed()) {
     thrower.Failed("", result);
   }
 
   if (result.val) delete result.val;
 }
 
-v8::internal::wasm::WasmModuleIndex* TranslateAsmModule(
+v8::internal::wasm::ZoneBuffer* TranslateAsmModule(
     i::ParseInfo* info, ErrorThrower* thrower,
     i::Handle<i::FixedArray>* foreign_args) {
   info->set_global();
   info->set_lazy(false);
   info->set_allow_lazy_parsing(false);
   info->set_toplevel(true);
 
   if (!i::Compiler::ParseAndAnalyze(info)) {
     return nullptr;
   }
@@ skipping 12 matching lines @@
     typer.set_allow_simd(true);
   }
   if (!typer.Validate()) {
     thrower->Error("Asm.js validation failed: %s", typer.error_message());
     return nullptr;
   }
 
   v8::internal::wasm::AsmWasmBuilder builder(info->isolate(), info->zone(),
                                              info->literal(), &typer);
 
-  auto module = builder.Run(foreign_args);
-
-  return module;
+  return builder.Run(foreign_args);
 }
 
 i::MaybeHandle<i::JSObject> InstantiateModuleCommon(
     const v8::FunctionCallbackInfo<v8::Value>& args, const byte* start,
     const byte* end, ErrorThrower* thrower,
     internal::wasm::ModuleOrigin origin) {
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
 
   i::Handle<i::JSArrayBuffer> memory = i::Handle<i::JSArrayBuffer>::null();
   if (args.Length() > 2 && args[2]->IsArrayBuffer()) {
@@ skipping 54 matching lines @@
     foreign = v8::Utils::OpenHandle(*local_foreign);
   }
 
   i::Handle<i::FixedArray> foreign_args;
   auto module = TranslateAsmModule(&info, &thrower, &foreign_args);
   if (module == nullptr) {
     return;
   }
 
   i::MaybeHandle<i::Object> maybe_module_object =
-      InstantiateModuleCommon(args, module->Begin(), module->End(), &thrower,
+      InstantiateModuleCommon(args, module->begin(), module->end(), &thrower,
                               internal::wasm::kAsmJsOrigin);
   if (maybe_module_object.is_null()) {
     return;
   }
 
   i::Handle<i::Name> name =
       factory->NewStringFromStaticChars("__foreign_init__");
 
   i::Handle<i::Object> module_object = maybe_module_object.ToHandleChecked();
   i::MaybeHandle<i::Object> maybe_init =
@@ skipping 120 matching lines @@
     int unused_property_fields = in_object_properties - pre_allocated;
     Handle<Map> map = Map::CopyInitialMap(
         prev_map, instance_size, in_object_properties, unused_property_fields);
 
     context->set_wasm_function_map(*map);
   }
 }
 
 }  // namespace internal
 }  // namespace v8